With lots of study in forums answered to the title, I am not able to solve. Please help !!!!
I am getting this when I run update via apt-get update every time.
I tried
sudo -i
apt-get clean
cd /var/lib/apt
mv lists lists.old
mkdir -p lists/partial
apt-get clean
apt-get update
The code does not work even after performing reboot
Also, I tried importing key
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 40976EAF437D05B5 and shows gpg unprocessed: 1
Distributor ID: Ubuntu
Description: Ubuntu 14.04.4 LTS
Release: 14.04
Codename: trusty